Seamus Flynn, a pharmacist and optometrist, says that Advil tends to have more side effects that can be “quite harsh on the stomach.” These side effects include upset stomach, nausea, vomiting, and heartburn, according to WebMD. Leann Poston, MD, a licensed physician and health advisor for Invigor Medical, says that chronic use of ibuprofen medications can actually damage the lining of the stomach, which produces more stomach issues like “stomach ulcers, pain, and bleeding.” Even the manufacturers of Advil suggest talking to your doctor before using Advil if you have a “history of stomach problems.” And for more warnings, If You’re Swallowing Your Medication With This, Stop Immediately. Both Advil and Tylenol work to reduce a fever, but you may want to still choose Tylenol when dealing with this symptom. Advil is a non-steroidal anti-inflammatory drug (NSAID), which directly targets pain caused by inflammation. So when you’re dealing with a non-inflammatory issue, like reducing a fever, “Tylenol is probably your better choice,” Poston says. And for medications to hold back on, If You’re Taking This OTC Medicine More Than Twice a Week, See a Doctor. If you have kidney problems, you should be reaching for Tylenol. According to Flynn, “Advil should not be used for people with kidney disease, as it can reduce the amount of blood flowing to the kidneys.” And long-term use of this type of medication can also negatively affect your kidneys. Per Flynn, long-term use of Advil “can cause a chronic kidney disease called chronic interstitial nephritis.” And for more up-to-date information, sign up for our daily newsletter. Mehmet Oz, MD, a cardiothoracic survey specialist and host of The Dr. Oz Show, says that Tylenol is broken down by the liver, while Advil is mostly broken down by the kidneys. Unfortunately, this means Tylenol can negatively affect your liver, especially if you’re already experiencing liver issues or are predisposed to liver problems. “Taking too much [Tylenol] may cause you to have liver damage, which can manifest as yellowing of the skin or whites of your eyes,” Oz explains. “You should be careful about taking Tylenol if you have issues with your liver, or if you drink a lot of alcohol, because alcohol is processed by the liver.” And if you’re worried about your liver, Drinking This Much Coffee Every Day Can Save Your Liver, Study Says. If your pain is due to inflammation, then Advil is “the better choice” because it is a NSAID, Poston explains. Jessica Nouhavandi, PharmD, lead pharmacist and founder of online pharmacy Honeybee Health, says that Tylenol doesn’t help with inflammation pain because “it does not have that anti-inflammatory effect.“ae0fcc31ae342fd3a1346ebb1f342fcb “Advil blocks the production of chemicals in the body that contribute to pain and inflammation—so whenever there is redness, swelling, heat, or pain at a site,” says Oz. “This makes it ideal for most back and neck pain, toothache, muscle sprains and strains, and menstrual cramps.” And for more health advice, If You Drink This, You Could Become Resistant to Antibiotics, Study Says.